The Wasilsi were a sentient humanoid species who inhabited the planet of Joralla. These beings were builders of temples and villages, skilled metalworkers, and possessed a written language. Joralla was also home to another sentient species, the avian Tikiarri, with whom the Wasilsi engaged in warfare for numerous years. Despite their superior strength and intelligence compared to the Tikiarri, the Wasilsi ultimately met their demise and became extinct. A sentientologist from the University of Huvveck proposed a theory suggesting that the Wasilsi were not originally from Joralla and that their extinction was caused by a plague.
The humanoid species known as the Wasilsi possessed a physical structure characterized by two arms and two legs. They had skeletons and, for a time, shared the planet of Joralla with the avian Tikiarri, over whom they had superior intelligent and strength. According to research conducted by Beyorth Gommdora, a sentientologist, the Wasilsi exhibited minimal structural similarities to the Tikiarri. This observation led Gommdora to hypothesize that the Wasilsi were not native to Joralla and therefore lacked inherent immunity to certain bacteria or viruses to which the Tikiarri were resistant.
The Wasilsi were an intelligent race of beings. They dwelled in villages, utilized gold and other precious metals, and fashioned artistic creations and metalwork. They developed their own system of writing, a written language, which they inscribed on parchment scrolls. The Wasilsi practiced a religion, which was expressed through the construction of temples and the creation of statues representing their deities. One particular temple's architecture featured an octagonal design, with walls that sloped inward towards a square apex. This apex was composed of four triangular sides and four rectangular sides. Symmetrical arrangements of various other features, including circular pillars, embellished the temple.
The Wasilsi made their home on the planet Joralla, situated within the Mektrun sector of the Mid Rim's. On this temperate world, the Wasilsi erected villages and temples, but their existence was marked by conflict with the Tikiarri, a primitive avian species. These two species engaged in numerous significant battles over many years, conflicts that the Wasilsi commemorated through artistic depictions on the walls of their structures. By the time the Battle of Yavin occurred, the Wasilsi had vanished, leaving behind only a few artifacts and the decaying remnants of their civilization, which by then were considered ancient, either buried or obscured by vegetation.
Beyorth Gommdora, a sentientologist from the University of Huvveck, dedicated his research to the study of the Wasilsi, although his investigations were complicated by frequent violent encounters with Tikiarri tribes. Given the Wasilsi's superior physical and intellectual capabilities compared to the Tikiarri, it was deemed unlikely that the avians were responsible for the eliminated of the Wasilsi. Instead, Gommdora proposed that the Wasilsi were not indigenous to Joralla but had either established a colony or suffered a crash landing on the planet. Subsequently, they were decimated by a plague against which the Tikiarri possessed immunity.
During the era of the Galactic Civil War, Adriav Kavos, an independent freighter captain, piloted his vessel to a clearing adjacent to a Wasilsi temple while attempting to negotiate a trade involving a valuable Rebel Alliance data disk. Kavos and his crew were subsequently ambushed by Tikiarri.
The Wasilsi were first introduced in Planets of the Galaxy, Volume One, released by West End Games in 1991.